From the state of the art, various embodiments of seat rail profiles are known. For example, seat rail profiles are used in conjunction with transverse girders to form the load-bearing structure of the floor frame within the fuselage structure of passenger aircraft. Apart from the static functions relating to the structure of the entire aircraft, and the bearing function relating to the floor panels, seat rails also provide a connection base for the attachment of further outfitting components or equipment elements, in particular passenger seats, toilet modules, galley modules, partition walls, trim elements, storage containers and the like. Generally, known seat rail profiles are extrusion molded from aluminum alloys. Seat rail profiles may also be used similarly in the construction of other passenger transport vehicles such as trains and ships.
Known seat rails usually comprise a reinforced profile crown, on the lower end or side of which support flanges or support surfaces are integrated as bearing surfaces for the floor panels. In other words, the support flanges protrude laterally from the bottom end or edges of the sides of the reinforcement zone, and the reinforcement zone protrudes upwardly above the upper surface of the support flanges. Also, the reinforced profile crown has therein an undercut groove so that attachment elements of the above-mentioned outfitting components can be inserted and locked into the groove at selected positions. Furthermore, the groove preferably comprises a locking arrangement, which makes it possible to position the outfitting components at defined grid dimensions in longitudinal direction of the groove, for example in grid dimensions of 2.54 centimeters or 1 inch, which is a dimension common in aircraft construction.
Between the top of the profile crown and the tops of the flanges there is a step or recess whose height preferably corresponds approximately to the thickness of the floor panels so as to ensure an essentially flat uninterrupted surface of the floor flushly aligned with the top of the reinforcement zone, that is formed in this way within the fuselage structure of the aircraft. In order to ensure the necessary bending resistance or stiffness, the base of the crown then leads to a central web, which in turn comprises flanges on its lower end, which flanges, depending on the design, can be used both for attaching the seat rail profile to the transverse girders and for ensuring the required rigidity.
Due to the design of the known seat rail profiles with a shoulder or recess in the region of the profile crown to receive the floor panels so that they are flush with each other, the floor panels cannot be positioned freely between the seat rails. The width that is possible for the floor panels is always specified and strictly limited by the distance between adjacent ones of the seat rails. Moreover, the further outfitting components intended for installation on the seat rails, in particular passenger seats, toilet modules, galley modules, partition walls, trim elements, storage containers or the like, need to have an attachment dimension at least across the longitudinal direction of the seat rail profile, which attachment dimension always corresponds to the spacing distance or to an integral multiple of the spacing distance between the seat rails. Implementing various equipment or outfitting variants in the passenger cabin is made difficult by this fixed grid dimensioning. Finally, the known embodiments are associated with an increased sealing effort, in particular in galley and sanitary areas such as toilet compartments or restrooms, because the region where the floor panels abut the seat rail profiles requires cumbersome and expensive sealing work.